Question / Help Recording Stream for Archive: Record then Encode vs Record

[billgates]

Hello everyone,

I need to record for archiving streaming movie that is encoded using 2-pass encoding at 5-6 Mbps. Media being streamed is about 1.5 hours long and original source is about 3.5 GB, so my question is:

1. Is it better to first Record stream using very high quality (CRF 0 or something) and then Encode?
2. Or record it with appropriate settings and if so what will be the best?

I’ve tried following:
Output Mode: Advanced
Encoder: x264
Rate Control: CRF
CRF: 20
Keyframe Interval: 2
CPU Usage Preset: superfast
Profile: high
Tune: film

I am using Intel NUC7i7bnh (Intel Core i7-7567U with Intel Iris Plus Graphics 650), 16 GB RAM, 512 GB 960 EVO SSD and Windows 10 Pro (page file, hibernate and updates are disabled during recording). Movie is being streamed in Firefox (60.0.2 64-bit) browser.

What I noticed is that during recording changing CPU Usage Preset from “superfast” to “veryfast” greatly reduces file size, but introduces lag (when playing video is not smooth) and skipped / dropped frames (about 5% based on the logs), so it not usable.

That is why I thought that maybe first recording and then encoding might give me the best quality / file size combination? Any suggestions?

Thanks

 

[koala]

Don't use OBS, don't use a screen recorder. You have a url as video source, so save it directly from the url to a file. Vlc can do this. This way you will not recode the footage but save exactly what is sent.

 

[billgates]

Don't use OBS, don't use a screen recorder. You have a url as video source, so save it directly from the url to a file. Vlc can do this. This way you will not recode the footage but save exactly what is sent.

It is not possible as video is DRM protected and there is no source URL that can be downloaded.